Uhmmm....... if it's from the 80's it's definitely old in terms of usual "MTBF" for most tires....
Despite how it's been stored or cared for, the materials making up the tire, especially anything rubber, would have hardened/dried up enough to negatively affect it's performance and durabilty. Light, oxygen, and pollution all conspire together or individually to break down the tires. I wouldn't use such old tires on the road IIWY. Just not worth the risk. You can still use them though for "wall hanger bikes"....